The recent developments in organic electrolyte systems have resulted in a large number of high energy-density primary cells based on lithium alloys. One of the major problems limiting the successful development of rechargeable versions of lithium cells is the nature of the lithium deposit during recharge of such cells. Investigations have indicated that lithium plating occurs in dendritic form in ordinary cells. According to the prior art this nature of the deposit causes a lowering of utilization efficiency and ultimately causes cell shorting. This shorting phenomena limits the cycle life of a rechargeable cell.
An object of this invention is to provide certain addition agents which can be introduced into the electrolyte of such rechargeable lithium cells which will eliminate the dendritic growth of lithium during the electrolytic plating of the lithium from the electrolytes of such cells.
As a further object, this invention provides a method for the non-dendritic plating of lithium from non-aqueous electrolyte systems.
A further object of this invention is to provide a cell and an electrolyte for such a cell which is capable of deposition of lithium in non-dendritic form.
We have discovered that we can eliminate the dendritic growth of lithium plating by incorporating certain addition agents into the electrolyte or into the cell itself.